from __future__ import annotations

from sqlalchemy import exists, select
from sqlalchemy.orm import Session, selectinload

from app.models.department import Department
from app.models.source_case import CaseBase, ScoringRule, TeachingCase, TraditionalCase


class SourceCaseRepository:
    """源库病例仓储：读取 case_base、traditional_case、teaching_case 和 scoring_rule。"""

    def __init__(self, db: Session) -> None:
        self.db = db

    def list_active_cases(
        self,
        department_id: int | None = None,
        case_type: str | None = None,
        mode: str | None = None,
    ) -> list[CaseBase]:
        """源库病例列表：按科室、病例分类和训练模式读取已发布病例。"""
        stmt = (
            select(CaseBase)
            .options(selectinload(CaseBase.traditional_case), selectinload(CaseBase.teaching_case))
            .where(CaseBase.status == 1, CaseBase.publish_status == 1)
        )
        if department_id:
            stmt = stmt.where(CaseBase.department_id == department_id)
        if case_type:
            stmt = stmt.where(CaseBase.case_type == case_type)
        normalized_mode = self.normalize_mode(mode)
        if normalized_mode == "practice":
            stmt = stmt.where(exists().where(TraditionalCase.case_id == CaseBase.id))
        if normalized_mode == "teaching":
            stmt = stmt.where(exists().where(TeachingCase.case_id == CaseBase.id))
        return list(self.db.scalars(stmt.order_by(CaseBase.id.desc())).all())

    def get_active_case_base(self, case_id: int) -> CaseBase | None:
        """源库病例详情：读取病例主表及传统/教学扩展表。"""
        stmt = (
            select(CaseBase)
            .options(
                selectinload(CaseBase.traditional_case),
                selectinload(CaseBase.teaching_case),
                selectinload(CaseBase.scoring_rules),
            )
            .where(CaseBase.id == case_id, CaseBase.status == 1, CaseBase.publish_status == 1)
        )
        return self.db.scalar(stmt)

    def get_department_name(self, department_id: int | None) -> str:
        """科室名称：按用户端 department 表读取科室名称。"""
        if not department_id:
            return ""
        department = self.db.scalar(select(Department).where(Department.id == department_id))
        return department.name if department else ""

    def get_scoring_rules(self, case_id: int) -> list[ScoringRule]:
        """评分规则：读取当前病例对应的基础评分细则。"""
        stmt = select(ScoringRule).where(ScoringRule.case_id == case_id).order_by(ScoringRule.id)
        return list(self.db.scalars(stmt).all())

    @staticmethod
    def normalize_mode(mode: str | None) -> str | None:
        """模式归一：旧 novice 请求按练习模式处理，第一版只暴露 practice/teaching。"""
        if mode == "novice":
            return "practice"
        return mode